Railway draft gear



April 28; 1959 E. H.IBLATTNER v RAILWAY DRAFT GEAR 2 Sheets-Sheet 1 Filed Sept. '16. 1953 Inventor: I Emil H. Blaitner his Attorney April 28, 1959 E. H. BLATTNER RAILWAY DRAFT GEAR 2 Sheets-Sheet 2 Filed Sept. 16, 1955 FIG. 6

Inventorf Emil H. Blattner his Attorney 35 FIG. 5

2,884,140 Ice Patented Apr. 28, 1959 RAILWAY DRAFT GEAR Emil H. Blattner, Williamsville, N.Y., assignor to The Symington-Gould Corporation, Depew, N.Y., a corporation of Maryland Application September 16, 1953, Serial No. 380,545

12 Claims. (Cl. 213-45) This invention relates to draft gears and has for its primary object the provision of an improved draft gear in which rubber and friction cushioning units are combined to produce a gear of exceptional capacity.

Another object of the invention is to provide an improved draft gear of high capacity in which rubber and friction cushioning units are arranged in tandem and act in parallel under load.

An additional object of the invention is to provide an improved draft gear fittable into an A.A.R. standard draft gear pocket and so combining rubber and friction cushioning units so as to have much higher capacity than draft gears now in general use.

A further object of the invention is to provide an improved draft gear having rubber and friction cushioning units arranged in tandem and acting in parallel for -high capacity and a second rubber unit acting in series 'for soft initial action and additional capacity.

A further object of the invention is to provide an improved draft gear having rubber and friction cushioning units contained in a housing and a follower formed as part of the draft gear, the follower containing a separate rubber cushioning unit for soft initial action and, with the units contained in the housing, providing a gear of high capacity.

Another object of the invention is to provide an improved draft gear of high capacity having counter-part end housings and contained cushioning units wherein the friction shoes of a friction unit common to the housings serve as the sole interlock therebetween.

Another object of the invention is to provide an improved draft gear utilizing rubber and friction cushioning units for high capacity, wherein the draft gear is held assembled by parts rigid with certain of its components.

Other objects and advantages of the invention will appear hereinafter in the detailed description, be particularly pointed out in the appeneded claims, and be .illustrated in the accompanying drawings, in which:

Figure 1 is a view partly in side elevation and partly in longitudinal section of a preferred embodiment of the draft gear of the present invention;

Figure 2 is a fragmentary view partly in plan and .partly in horizontal section of the draft gear of Figure 1;

Figure 3 is a transverse sectional view taken along the lines 3 -3 of Figure 1;

Figure 4 is a view partly in side elevation and partly in longitudinal section of a second embodiment of the draft gear of the present invention;

Figure 5 is a transverse sectional view taken along the lines 55 of Figure 4;

Figure 6 is a transverse sectional view taken along the lines 66 of Figure 4; and

Figure 7 is a fragmentary longitudinal sectional view showing a step in the assembly of the draft gear of Figure 4.

Referring now in detail to the drawings, in which like reference characters designate like parts, both of the illustrated embodiments of the draft gear of the present invention are adapted to be mounted between the draft sills (not shown) of a railway car and are especially designed to fit into the standard draft gear pocket of 24%" and, within the standard travel of 2 /2" to have a capacity in excess of 30,000 ft. lbs. In both modifications this high capacity is obtained by utilizing a combination of rubber and friction cushioning units.

Rubber, alone, or when bonded to metal, has high ultimate capacity but with little energy absorption and very considerable energy absorption is desired in the cushioning units of both types in the draft gear of the present invention. It is therefore contemplated to employ rubber cushioning units of the kind having good frictional characteristics and the term cushioning unit, as herein used, connotes a unit having such characteristics, whether friction or rubber. These plurality of cushioning units, at minimum, at least one of each type, are arranged in tandem and so related that at least two, including one of each type, act in parallel. In each embodiment of the invention the friction cushioning unit acts against one or more cast housings, each containing a rubber cushioning unit.

As to details, reference will first be made to the embodiment of Figures 1-3. The draft gear of this embodiment is counterpart or symmetrical about its vertical center line and is comprised of a pair of friction housings, casings or barrels 1, of substantially box-shape, one at either end of the gear. Each of these housings is formed, longitudinally, of top and bottom walls 2 and side or connecting walls 3, the walls also being connected at one end by an integral end wall 4 closing the outer end of the housing. Each of the housings is open at its other or inner end and has formed on the inner confronting faces of each of its upper and lower walls 2 an outwardly sloping or inclined friction or wedging surface 5, the surfaces of each housing sloping oppositely and diverging or flaring toward its open end. Each of these surfaces terminates inwardly of the housing in an instanding transversely disposed shoulder or abutment 6.

Within the pocket, recess or cavity 7 defined by the several longitudinal walls 2, 3, and 4 of each housing 1 and inwardly of the shoulders 6, is adapted to fit or seat a rubber cushioning unit, designated generally as 8. As best shown in Figure l, the cushioning unit is made up of rubber spring elements 9 alternating longitudinally with and divided or separated by separating or spacer disks, plates or elements 10. The spring elements 9 are each formed of a center disk or plate 11 and connected rubber pads 12 disposed on either side of the center disk, the rubber pads being molded about the disk and bonded to each other through holes 13 formed in the plate, but detached from and movable laterally to frictionally engage the faces of the included disk on being compressed. The rubber pads also spreading laterally over and frietionally engaging the faces of the spacer plates 10 under like conditions, it is evident that the rubber cushioning unit 8 has good frictional characteristics and very considerable energy absorption under load, thus particularly suiting it for use as a cushioning unit in the-draft gear of the present invention.

The rubber cushioning unit 3, while insertible into the pocket 7 through a suitable slot (not shown) in a longitudinal wall of the housing, to avoid the necessity of subsequently closing such a slot in part or whole, preferably is designed to be inserted element-wise into the pocket through the open end or bell-mouth 14 of each housing. So that the last of the elements may readily be inserted the height of the plates is made somewhat less than that of the recess. To take up part of this difference and prevent excessive lateral movement of the plates, ribs 15 are provided within the recess, each instanding from one of the upper and lower walls 2 and overand underlying the cushioning unit in its assembled position.

The rear end of the rubber cushioning unit 8 bears at its rear or outer end directly against the inner face of the end wall 4 of the associated housing. The front or inner end of the unit is acted on by a floating follower, follower block or plate 16 seating or fitting in the pocket 7 within the shoulders 6. Bearing on and adapted to frictionally rub or wipe against the other, inner or front face 17 of the floating follower 16 in each of the housings 1, are the confronting transversely directed planar end faces 18 of a pair of counterpart friction shoes or wedges 19 forming part of a friction cushioning unit 20, the wedges being common to and serving to connect the housings in a manner to be hereinafter described.

Each of the wedges 19 is provided with a pair of preferably flat friction wedging faces 21, which are oppositely inclined or sloping and diverge inwardly transversely of the draft gear. Each of these faces corresponds in configuration and is adapted to frictionally engage and wipe or rub against one of the sloping friction or wedging surfaces on the housings 1. The sloping surfaces of each wedge are spaced at the center and each merges at its outer end in a transversely directed and outstanding lip, lug or flange 22, the several lips 22 with the shoulders 6 serving to interlock the wedges and housings in the assembled position of the draft gear and limit the outward movement of the cushioning components relative to and connect the housings. Between the wedges and acting transversely or laterally of the draft gear thereagainst to urge their sloping surfaces into frictional engagement with the wedging surfaces 5 on the housings, are the spring means of the friction cushioning unit 20, preferably in the form of a pair of opposed sets of semi-elliptical leaf springs 23, the sets being arranged back-to-back and bearing at their ends against the inner or confronting faces 19a of the wedges.

To assemble the gear, the wedges 19 and leaf springs 23 of the wedge unit are compressed in a press and the housings 1, with their cushioning units 3 and floating followers 16 already inserted, are then threaded over the ends of the wedge unit and thereafter compressed longitudinally practically to full closure, so that the wedge lugs 22 pass inwardly beyond the shoulders 6 on the housings. Release of the lateral pressure on the wedge unit and end pressure on the housings would then cause the force of the several springs to expand the gear and move the wedges and housings to interlocking position.

However, it is preferred that the draft gear initially be of less than full length to facilitate its installation in a standard A.A.R. draft gear pocket. For this purpose, the end pressure on the housings is maintained after the wedge unit is released and precompression blocks (not shown) of friable material are inserted between the thenspaced interlocking lugs and shoulders. This effectively shortens the draft gear for installation and the blocks, since friable, disintegrate after a few service impacts, enabling the gear to expand to full pocket length. Thereafter, the draft gear, by virtue of the spacing between the confronting ends of its housings, provides the standard 2 /2 of travel. For better operation it is preferred that a separate front follower (not shown), such as an A.A.R. standard follower, be interposed between the housing used as the front end of the draft gear and the related coupler (not shown).

In operation, longitudinal forces on buff or draft are transmitted to the housings 1, causing the latter, through their wedging surfaces 5, to compress the wedges 19 against the force of the leaf springs 23, this compression also being resisted by the friction engendered between the wedging faces 21 on the wedges and wedging surfaces 5 on the housings and that resulting from the inward rubbing of the outer end faces 18 of the wedges on the front faces 17 of the floating followers 16. Since the wedges maintain their longitudinal dimensions under load,

they serve as a rigid column which transmits the load directly to the two rubber cushioning units 8, the three units, although arranged in tandem, thus all acting in parallel. As the draft gear approaches full closure its capacity increases rapidly due to the rubber pads 12 of the rubber cushioning units, its maximum capacity, as previously mentioned, being in excess of 30,000 ft. lbs., and more than adequate for service conditions, present or contemplated.

The draft gear of the second of the illustrated embodiments, that shown in Figures 4-7, is an improvement of the draft gear of my Patent No. 2,540,041 of January 30, 1951. In this form of draft gear one main friction housing, casing or barrel 25 is used, and the draft gear, though adapted to fit into the standard draft gear pocket, dispenses with the standard A.A.R. front follower block, using instead, a front follower 26 formed as part of the draft gear.

The friction housing 25 is of the same general construction as the housings 1 of the first embodiment, being closed at one end and open at the other and having an interior pocket or cavity 27 for the reception of a rubber cushioning unit 28 of the same type and a floating follower, follower plate or block 29. Bearing against the floating follower 29 and rubbing or wiping on its front face 30 are a pair of counterpart friction wedges or shoes 31 of the friction cushioning unit 32, the wedges being urged laterally or transversely of the housing by a pair of sets of semi-elliptic leaf springs 33. However, unlike the wedges of the first embodiment, those 31 of this embodiment are enclosed or contained entirely within the housing 25. To obtain a capacity in the friction unit 32 substantially equal to that of the corresponding unit 20 of the first embodiment, each of the wedges 31 is provided with a pair of inclined or sloping, preferably flat, friction faces 34, the friction faces, since acting against the same housing 25, being substantially parallel and in stepped relation. The friction faces 34 of each wedge bear against and frictionally engage a pair of corresponding wedging surfaces 35 formed on the inner face of each of the upper and lower walls 36 of the housing 25. These wedging surfaces 35 are outwardly inclined or sloping, the companion surfaces on the two walls flaring or diverging outwardly and providing the housing with a double bell-mouth 37.

With the wedging faces 34- and surfaces 35 stepped as described, the intervening connecting portions of the walls of the wedges 31 and housing 25 provide transversely overlapping and directed shoulders or abutments, those on the wedges being designated as 38 and on the housing as 39. These outstanding shoulders 38 on the wedges and instanding shoulders 39 on the housing are thus adapted to interlock and lock or hold the rubber and wedge cushioning units 28 within the housing 25 when the draft gear is assembled, as well as to limit the outward movement of these units relative to the housing.

Although described as providing the housing 25 with a double bell-mouth 37, the wedging surfaces 35 actually are disposed some distance within the housing, the longitudinal upper and lower walls 36 and side or connecting walls 40 extending somewhat beyond the wedging surfaces to provide a preferably rectangular opening 41 in which seats or nests the aforementioned front follower 26. While formable, like the front follower of my Patent 2,540,041, of a unitary casting, the front follower of the instant draft gear preferably is employed not only to transmit force from the butt of a coupler (not shown) to the wedges 31, but to augment the capacity of the draft gear. To this end the front follower may be formed of two main parts, one part or member, a casing or housing member 42 bearing, rearwardly, directly against the wedges 31 and cupped, socketed or recessed to provide a forwardly opening recess or socket 43, and the other part or member, a front follower plate or block 44 laterally overlapping the casing member and having HAM.

s, a, restricted neck 45 fitting, seating or. nesting in the recess 43.

Interposed between the follower block 44 and the rear wall 4,6 of the casing member 42 and contained within the recess is. a rubber cushioning unit 47 of the same type as the main cushioning unit 28 within the housing 25,,but composed of a lesser number of spring units of smaller lateral dimensions because of space limitations. For holding the front follower in assembled relation, there may be provided a connecting bolt 48 extending centrally through the rear wall 46 of the casing member 42, follower block 44 and interposed rubber cushioning unit 47, longitudinally of the draft gear, the bolt having, its head 49 fixed, as by Welding, to and rigid with the casing member and having a sliding fit with the follower block 44 and cushioning unit 47, maximum outward, telescoping of the nested parts being determined by engagement of the associated nut 50 with the follower blocku As. shown, the head 49 and nut 50 are inset the casing member and follower block, respectively, toprevent interference with associated parts. It is also desired that thefollower block 44 be anglable, against the follower cushioning unit 47, relative to the remainder of the draft gear, the disclosed tolerances in its conuec ion being provided for this purpose.

While the front follower 26 may be locked directly to the housing 25, it is preferably interlocked with the wedges 31, for holding it in assembled relation. To this end there may be formed on the casing member 42 apair of transversely spaced interlocking or locking fingers or'lugsv 51 extending rearwardly or inwardly of the end wall 46 of the member and having their inner ends instandingor bent inwardly transversely of the draft gear. To receive these fingers 51 the outer edges 52 of the two wedges 31 are slotted, as at 53, so that each finger can fit or seat within one of the slots 53 and overlap, laterally of the draft gear, a web 54 forming the front vertically directed wall of the associated wedge.

-In assembling the draft gear of this embodiment the main rubber cushioning unit 28 and the floating follower .29. rnay be inserted, element-wise, into the pocket 27 and the friction cushioning unit 32, comprised of the wedges 31 and leaf springs 33, may be fitted, while laterally compressed, into its seat within the bell-mouth 37 of the housing 25. By then applying pressure against the outer ends of the wedges 31, the latter may be forced in sufficiently to enable assembly blocks 55 to be inserted through the lateral openings 56. These blocks hold the shoulders 39 on the housing and 38 on the wedges in spaced relation and the leaf springs 33 compressed, so that the fingers 51 on the front follower 26 may, be inserted in the slots 53 in the wedges 31. Further compression of the gear then releases the assembly blocks and subsequent release of the compressive force causes the several. components of the gear, under the force of the springs, to move to interlocked position. As in the first embodiment the rubber pads and leaf springs of the cushioning units of this embodiment are placed under suflicient initial compression to maintain the parts in assembled relation. I The operation of the gear of this embodiment is similar to that of the first embodiment in the parallel action of the friction and main rubber cushioning units, 32 and 28, respectively. However, the third cushioning unit 47, contained in the front follower 26, although arranged in tandem with the other cushioning units, acts in series therewith and, since the first of the units to receive the bufling or draft forces, affords to the gear both additional capacity and soft initial action.

From the above detailed description it will be apparent that there has been provided an improved draft gear of high capacity, both of the illustrated embodiments of the I at having a capacity in excess of 30,000 ft. lbs., which QQhtains such capacity by the use of two or more cushionin'g' units' arranged in tandem, the gears combining rubber and friction cushioning units, some or all of which act in parallel, and the high capacity being obtainable within the space limitations of the standard A.A.R. draft gear pocket. It should be understood that the described and disclosed embodiments are merely exemplary of the in,- vention and all modifications are intended to be included which do not depart either from the spirit of the invention or the scope of the appended claims.

Having described my invention, I claim:

1. A draft gear comprising a pair of counterpart housings closed at their outer ends and having confronting open inner ends, a rubber cushioning unit within each housing, wedge means extending into and connecting said housings and acting longitudinally on said rubber cushioning units for transmitting force therebetween, and spring means acting laterally on said Wedge means for urging said means into wedging engagement with said housings.

2. A draft gear comprising a-pair of counterpart housings closed at their outer ends and having confronting open inner ends, a rubber cushioning unit within each housing, wedge means extending into and connecting said housings and acting longitudinally on said rubber cushioning units for transmitting force therebetween, spring means acting laterally on said wedge means for urging said wedge means into wedging engagement with said housings, and means on said housings and wedges for limiting out- Ward movement of said wedges relative thereto.

3. A railway draft gear comprising a. pair of counterpart housings arranged in tandem and having closed'outer ends and open confronting ends, a rubber cushioning unit within and disposed longitudinally of each of said housings, a floating follower in each of said housings outwardly of and acting on the associated cushioning unit, a pair of counterpart wedges extending into the open ends of said housings and acting on outer faces of said floating followers, spring means between and acting laterally on said wedges for urging said wedges into frictional engagement with wedging surfaces in said housings, and means associated with said wedges and housings for limiting relative outward longitudinal movement therebetween,

4. A railway draft gear comprising a pair of counterpart housings arranged in tandem and having open confronting ends and closed outer ends, a pocket in eachof said housings intermediate ends thereof, a rubber cushioning unit extending longitudinally of each of said housings and contained within the pocket thereof, a floating follower in each of said pockets outwardly of said rubber unit and disposed transversely of said housing, outwardly flaring wedging surfaces in each of said housings adjacent the open end thereof, abutment means connected to and disposed inwardly of each of said wedging surfaces and instanding from longitudinal walls of said housings, transversely spaced counterpart wedges extending into the open ends of and connecting said housings, each of said wedges having outwardly facing oppositely inclined .wedging faces each engaging one of said wedging surfaces on said housings, laterally directed surfaces on opposite ends of each of said wedges and having rubbing contact with outer, faces of said floating followers, lug means on said wedges overlapping and each associated with one of said rubbing surfaces, said lug means overlapping said abutment means on said housing for interlocking and limiting maximum longitudinal extension of said draft gear, and a pair of sets of leaf springs arranged back-to-back and acting laterally on said wedges for urging said wedges into frictional engagement with said wedging surfaces on said housing.

5. A draft gear comprising a housing open at one end and having a pocket therewithin, a pair of spaced .outwardly flaring wedging surfaces formed on inner faces of and instanding from opposite longitudinal walls of said housing and together restrictingthe opening into said pocket, a rubber cushioning unitwithinsaid pocket and formed of alternate rubber spring and spacer elements, a floating follower within said pocket outwardly of said rubber unit, said rubber unit and follower being of such lateral dimensions as to be insertible element-wise into said pocket between said wedging surfaces, rib means extending longitudinally of and instanding from said longitudinal walls within said pocket for limiting lateral movement of said rubber unit and follower relative to said housing, counterpart wedges in rubbing contact with an outer face of said follower and having wedging faces adapted to frictionally engage said wedging surfaces, and spring means between and acting laterally on said wedges for urging said wedging faces and surfaces into engagement.

6. A draft gear comprising a housing open at one end, a rubber cushioning unit within said housing and having an end bearing against a closed end thereof, a floating follower within said housing outwardly of and bearing against an opposite end of said rubber unit, a pair of counterpart wedges within said housing and each frictionally engaging wedging surfaces on said housing and having rubbing contact with said floating follower, spring means within said housing and acting laterally on said Wedges for urging said wedges into said engagement with said housing, a front follower extending into the open mouth of said housing and having a follower element in engagement with outer ends of said wedges, said follower element having an outwardly opening recess, a front follower plate having a restricted portion extending into said recess in said follower element, a rubber cushioning unit within said recess between said follower element and plate, and means connecting said housing, wedges, follower element and plate for limiting maximum longitudinal extension of said draft gear.

7. A draft gear comprising a housing open at one end, a rubber cushioning unit within said housing and having an end bearing against a closed end thereof, a floating follower within said housing outwardly of and bearing against an opposite end of said rubber unit, a pair of counterpart wedges within said housing and each frictionally engaging wedging surfaces on said housing and having rubbing contact with said floating follower, spring means within said housing and acting laterally on said wedges for urging said wedges into said engagement with said housing, a front follower extending into the open mouth of said housing and having an element in engagement with the outer ends of said wedges, a socket in said element having an outwardly opening recess aligned axially with said pocket in said housing, a front follower plate nesting with said follower element and having a restricted portion extending into said socket thereof, a rubber cushioning element within said socket between said follower element and plate, means connecting said follower element and wedges to said housing and limiting outward longitudinal movement thereof relative thereto, and means connecting said follower element and plate for allowing limited relative longitudinal and angling movement thereto.

8. A draft gear comprising a housing, a rubber cushioning unit within said housing, spaced wedge means in said housing outwardly of said rubber unit, spring means acting laterally on said wedge means for urging said wedge means into frictional engagement with said housing, a floating follower interposed between and bearing against said rubber unit and wedge means, a front follower in said housing outwardly of and acting on said wedge means, and a second rubber cushioning unit associated with said front follower, said cushioning units and wedge means being arranged in tandem and at least one of said cushioning units and said wedge means acting in parallel under load.

9. A railway draft gear comprising a housing, a rubber cushioning unit within said housing, a pair of spaced wedges in said housing outwardly of said rubber unit, spring means acting laterally on said wedges for urging said wedges into frictional engagementwithrsaid housing, a floating follower interposed between said wedges and rubber unit, housing means connected to said wedges, and a second rubber cushioning unit within said housing means, said cushioning units and wedges being arranged in tandem and at least one of said cushioning units acting in parallel with said wedges under longitudinal load.

10. A railway draft gear comprising a housing, a rubber cushioning unit within said housing, a pair of spaced wedges in said housing outwardly of said rubber unit, spring means acting laterally on said wedges for urging said wedges into frictional engagement with said hous-' ing, a floating follower interposed between said wedges and rubber unit, front housing means connected to said wedges, and a second rubber cushioning unit in said front housing means, said cushioning units and wedges being arranged in tandem and at least one of said cushioning units acting in parallel with said wedges under longitudinal load.

11. A railway draft gear comprising a housingopen' at one end, outwardly flaring wedging surfaces on inner faces of confronting longitudinal walls of said housing, a pocket in said housing inwardly of said wedging surfaces, a rubber cushioning unit within said pocket, a pair of transversely spaced wedges in said housing outwardly of said rubber unit and having wedging faces engage said wedging surfaces on said housing, spring means interposed between and acting transversely on said wedges for urging said wedges into frictional engagement with said housing, a floating follower interposed between said wedges and rubber unit, a front follower projecting into said housing and bearing against outer ends of said wedges, transversely disposed abutment means on said wedges and housing and associated with said wedging faces and surfaces for limiting outward movement of said wedges relative to said housing, and means on said front follower and fitting into and transversely overlapping said outer ends of said wedges for maintaining said front follower in assembled relation with said wedges and housing.

12. A railway draft gear comprising a housing open at one end, outwardly flaring wedging surfaces on inner faces of confronting longitudinal walls of said housing, a pocket in said housing inwardly of said wedging surfaces, a rubber cushioning unit within said pocket, a pair of transversely spaced wedges in said housing outwardly of said rubber unit and having wedging faces adapted to engage said wedging surfaces on said housing, spring means interposed between and acting transversely on said wedges for urging said wedges into frictional engagement with said housing, a floating follower interposed between said wedges and rubber unit, a front follower projecting into said housing and bearing against outer ends of said wedges, transversely disposed abutment means on said wedges and housing and associated with said wedging faces and surfaces for limiting outward movement of said wedges relative to said housing, slots in outer edges of said wedges, and fingers on said front follower and each received in one of said slots and adapted to transversely overlap a portion of a front end of the associated wedge for limiting outward movement of said front follower relative to said wedges and housing. 1

References Cited in the file of this patent UNITED STATES PATENTS 2,053,940 Blattner Sept. 8, 1936 2,054,566 Swan et al. Sept. 15, 1936 2,233,348 Light Feb. 25, 1941 2,540,041 Blattner Jan. 30, 1951 2,649,213 Withall Aug. 18, 1953 2,656,936 Danielson et al. Oct. 27, 1953 2,686,667 Willison Aug. 17, 1954 2,720,320 Dentler Oct. 11, 1955 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2,884,140 April 28, 1959 Emil H. Blattner It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected beloW..

In the grant, lines 2 and 3, for "assignor to The SymingtonGould Corporation, of Depew, New York, -a corporation of Maryland," rea assignor to Symington Wayne Corporation, a corporation of Mar land, line 12, for The Symington-Gould Corporation, its successors" rad Symington Wayne Corporation, its successors in the headiig to the printed specification, lines 3, 4 and 5, for "assignor to The sylington- Gould Corporation, Depew, N Y, a corporation of Maryland" read assignor to Symington Wayne Corporation, a corporation of Marrland -e Signed and sealed this let day or December 1959.

(SEAL) Attest:

KARL AXLINE ROBERT c. WATSON Attesting Officer 7 Y Comnissioner. of Patents 

